Plunger extension for disposable ampoules



O Umted States Patent [1113548324 [72] Inventor ByronJ. Carr 1,179,561 4/1916 Reed 128/218(P) East Greenbush, NY. 2,420,102 5/1947 Shuford 128/218 [2 pp 689536 FOREIGN PATENTS 3? g d g {3% 19,848 1912 Great Britain 128/2181 2225; smjunmg in 133,517 7/1949 Australia 128/218(P) I New York, NY. 71,992 12/1950 Denmark 128/218(P) a corporation of Delaware Primary Examiner-Richard A. Gaudet Assistant Examiner-Channing L. Pace Attorney-Charles R. Fay [54] PLUNGER EXTENSION FOR DISPOSABLE AMPOULES 1 Claim, 3 Drawing Figs.

[52] U.S. Cl 128/218 151] 1111. C1. A6lm 5/28,

1 1/06 ABSTRACT: An extension for the plunger of a cartridge or 0r ampoule containing a medicament to be injected e g a sy. 218, 218(P), 218(PA), 218.1, 218.2, 234, 235 ringe, the extension being specifically for the purpose of extending the length of the cartridge plunger in cases where a [56] References cmd relatively small amount of medicament is provided, to prevent UNITED STATES PATENTS the plunger from being withdrawn into a nonsterile area in the 2,966,910 1/1961 Camber 128/2l8.l cartridge by the use of the syringe, e.g. in aspirating.

PATENTEU DEC22 1970 FIG.

INVENTOR B. J. CARR ATTORNEY PLUNGER EXTENSION FOR DISPOSABLE AMPOULES This invention relates in general to disposable cartridges or ampuls for use with a syringe, the specific improvement residing in the provision of an inserted extension member for connection to a plunger in the cartridge or ampul, said extension being connectable with relation to the plunger of the syringe in effect spacing the cartridge plunger from the inner endof the syringe plunger so that it is impossible for the syringe plunger to be withdrawn to an extent to bring the cartridge plunger into anarea in the cartridge which might not be 'sterile. In cases where the needle is inserted and aspiration is performed, and when medicament is of a relatively small content with relation to the length of the cartridge itself, it often happens that the plunger is withdrawn into a nonsterile area in the cartridge, but by the use of the new insert extension, this is prevented.

Other objects and advantages of the invention will appear hereinafter.

Reference is to be had to the accompanying drawings in which:

FIG. 1 is a view in elevation illustrating an ampul to which the invention may be applied;

FIG. 2 is a longitudinal section showing the syringe plunger in position to actuate the cartridge plunger; and

FIG. 3 is a section on line 3-3 of FIG. 2 on a larger scale.

In FIG. I there is shown a disposable cartridge or ampul l usually made of glass or some similar suitable material, the same having a reduced, forwardly projecting neck 12 together with a crimped-on metal cap 14 holding the usual diaphragm 16, see FIG. 2. A needle 18 in a needle hub 20 having an end cap 22 has its inner end in position to pierce the diaphragm in the usual manner.

This entire cartridge is adapted to be placed in the barrel of a syringe (not shown) and injection or aspiration is made in the normal manner, it being understood that the end of the cartridge or ampul at 24 is open for the reception of the plunger 25 of a conventional medical or dental syringe, which can be attached to the cartridge plunger 26 by a threaded member 30-on the cartridge plunger 26, to inject medicament 28, more or less as usual. However, in the present case the cartridge plunger is located intermediate the ends of the cartridge or ampul rather than adjacent the open end 24 thereof. The

. reason for this is that in this case only a relatively small amount of medicament is desired to be injected, in comparison with a more normal dosage of the medicament, in which case the cartridge or ampul would be substantially full.

With a full ampul, the entire interior is sterile; but in the case shown in FIG. 2 the portion of ,the interior of the cartridge or ampul 10 which is to the left of the cartridge plunger 26 may be nonsterile and under inspiration, the medicament 28 might possibly be contaminated.

' However, with the novel insert generally indicated at 32 interposed between cartridge plunger 26 and the inner end of plunger 25 of the syringe and connected by means, for in stance, of the screw-threaded member 34 or some other means, the general interior of the cartridge or ampul is kept sterile.

The insert is of a size and shape to substantially fill the barrel or bore of the cartridge and can be inexpensively made of plastic or some suitable material, using only a small amount of such material because it is hollow. The insert can be made in different lengths for different applications.

Although threaded members at 30 and 34 are shown with male and corresponding female members for connection of the syringe plunger 25 with respect to the cartridge plunger 26 through the insert 32, other forms of connections are considered to come within the scope of the invention.

Through the use of the insert 32 or like means, a single size of cartridge or ampul 10 may be utilized for containing an amount of medicament 28 which may be desired for a oneshot injection. In addition, it is easier to connect the syringe plunger 25 with respect to the member 341 on the insert than with respect to the plunger fastener member 30 in cases where only the amount of medicament shown in FIG. 2 IS utilized in the cartridge or ampul. In this case the cartridge may be two or three times longer than is necessary, but at the same time this avoids the necessity of making ampuls of different length for different dosages. Y

I claim:

1. An ampul comprising an elongated tubular member having a necked-in portion adjacent one end thereof, a diaphragm closing said end and held thereon by a metal cap crimped over the necked-in portion, a needle-carrying hub attached to the cap with the inner end of the needle'piercing the diaphragm, the other end of the tubular member being open, a plunger positioned in the mid portion of the member and confining a quantity of medicament between itself and the diaphragm, an elongated tubular extension slidably fitted within said tubular member and extending from the plunger to a portion of the tubular member adjacent its open end, means securing the inner end of the extension to the plunger and means securing the outer end of the extension to a plunger-operating element extending into the open end. 

